In Afghanistan, the landscape itself rises up against invaders, its soft limestone caverns, stunning granite mountains and subterranean streams offering Afghan fighters countless underground places from which to elude and harass foreign armies. From ancient irrigation systems to caves that go on for miles, the country's underground labyrinths have confounded would-be conquerors since the days of Genghis Khan. They helped Afghan guerrillas defeat British imperialists in the 19th century and drive out the Soviets in the 20th. Now it's America's turn. President Bush has vowed to "smoke out" Osama bin Laden and the Taliban rulers who give him shelter. Already, U.S. forces are targeting the caves and other underground complexes. Reports indicate they are attacking from the air with "bunker-busting" bombs. It's almost certain, if they haven't already, that U.S. commandos will follow once they believe they know where bin Laden is.
Media reports over the weekend suggested that U.S. intelligence has narrowed bin Laden's whereabouts down to a handful of underground hideaways in eastern Afghanistan. Driving the enemy out of their lairs is a difficult and dangerous task. Just finding the right hideaways is hard enough maybe impossible without help from sympathetic Afghans. Then U.S. troops must avoid ambushes in deadly mountain passes, overcome treacherous winter weather and avoid blundering into the booby traps and mines that Afghan fighters have turned into a macabre form of art. Completing a successful military operation against the caves and other hideaways isn't impossible. U.S. troops are better trained and better equipped than those who came before them. They use infrared sensors to spot and target cave dwellers huddled around underground campfires. And the "bunker-busting" bombs can crumble some, but not all, of the country's underground lairs.

But first they have to find what they are looking for. "We have caves even the Devil himself doesn't know about," former mujahedin fighter Zaidullah Qaumi says. "Caves were our best heavy weapon." He once spent 2 days with 10 other fighters crouched in a lair near a subterranean stream, listening to Soviet troops search futilely for them aboveground. Perfect for guerrilla warfare Afghanistan's rugged terrain is ready-made for guerrilla warfare.

Start with extensive networks of limestone caves. Some have tunnels that lead down thousands of feet or extend for miles horizontally, says Jack Shroder, a University of Nebraska geologist who specializes in Afghanistan's caves. Then there are man-made caves. The oldest are karez, irrigation tunnels built before Alexander the Great entered Afghanistan more than 2,300 years ago. They were constructed by farmers desperately seeking water beneath a parched landscape. The tunnels make good hiding places.

Afghans cowered in the karez when Genghis Khan's Mongol hordes roared through the country in 1221, killing anyone they saw. Fighting Soviet invaders who sought in vain to prop up the puppet regime of Afghan President Najibullah in the 1980s, mujahedin rebels expanded the karez, adding special storage tunnels for ammunition and supplies. Many of the underground bunkers are even more ambitious.

Afghan rebels started building them in the 1980s, under granite thousands of feet inside mountains. They can be more than 2 stories high and wide enough to park 18-wheelers inside. "Even if they bombed us, we wouldn't even know it because we were down so deep," Qaumi says. "We weren't even afraid of an atom bomb." Bin Laden and his Arab followers later occupied and expanded these compounds, sealing them with steel doors and reinforcing the interiors with concrete. America's 5,000-pound bunker-busting bombs are useless against some of these compounds. Two of the three biggest are near Jalalabad, a major city on Afghanistan's northeast border with Pakistan near a key crossing point for refugees leaving the country.

The other, experts say, is north of the Taliban stronghold Kandahar. During the Afghan-Soviet war, former mujahedin commander Ahsan Ullah met bin Laden at an underground complex near Khost, in Paktia province along the Pakistani border. Behind buildings set in a mountainside, bin Laden had tunneled into the rock, Ullah recalls. The interior was carpeted and furnished, the temperature controlled by heaters and air conditioners, the electricity cranked out by generators.

Different problems posed

The different subterranean lairs and dugouts pose different problems to invading troops. The karez and simple shelters gouged out of the earth give Afghan fighters a place to store small caches of supplies and weapons, take short rests, find shelter from enemy bullets and stage guerrilla operations in which they seemed to materialize out of nowhere and vanish. "When you come, there is nobody," recalls a former Afghan colonel in the Communist army. "But when you leave, they come out and attack you from behind." The larger underground bunkers give fighters a place to store more and bigger weaponry and to hide more people for longer periods, allowing them to survive bombing raids in relative comfort. Consider the Zhawar complex in Paktia province. In 1986, the compound withstood 57 days of bombardment before the mujahedin finally abandoned it.

The advancing Soviets were astonished by what they found inside. Mujahedin rebels had built an underground mosque with an ornate brick facade; a hospital with an ultrasound machine; a grease pit occupied by a T-34 tank; a library stocked with books in English and Farsi; and a subterranean hotel furnished with comfy chairs and plush carpets. The compound had 41 spacious caves and tunnels the length of six football fields. "How many of our aircraft had worked this site over and the hotel and caves were still intact," marveled Viktor Kustensko, a Soviet witness to the 1986 incident, in a article he wrote in 1996 for Soldat udachi, the Russian version of Soldier of Fortune magazine. After being used by the mujahedin, the Zhawar compound was occupied and expanded by bin Laden and then bombed ineffectually by the Americans in retaliation for the bombings of two U.S. embassies in Africa in 1998.

The colonel, who requests anonymity because he lives illegally in Pakistan, says he and his comrades would search for underground hideouts by pounding their feet or the butts of their Kalashnikovs against the ground in suspicious spots, listening for a hollow sound. That low-tech approach was only sometimes successful: Informants were by far the best way to root out mujahedin caves. Captured rebel fighters would be persuaded either by torture or promises of freedom to lead Soviet soldiers to the hideouts. The informants were concealed in sheets to protect their identities in an effort to prevent reprisals.

The colonel recalls arranging for one informant to be spirited away to a hidden location with his family, while the government-controlled media published a bogus report of his death a Soviet-style witness relocation program.

The caves are good for hiding guerrillas and storing supplies, but not for fighting. "A cave can protect people from airstrikes," says Afghan journalist Ali Jalali, who fought alongside the mujahedin against the Soviets. "But fighting in a cave is not something you would do. ... The cave can become a tomb for the people inside." Soviets' brutal methods The Soviets often dealt brutally with rebels hiding in caves, using flame-throwers among other things.

In 1982, Soviet troops found Afghans hiding in a karez in Logar Province, in eastern Afghanistan. Wearing gas masks, the Soviets poured gasoline, diesel fuel and an incendiary white powder into the tunnel and set it alight, incinerating 105 men, women and children, Jalali and military analyst Lester Grau wrote in a history of the mujahedin-Soviet war. At first, the mujahedin would often open fire at Soviets trying to enter their caves. But the Soviets and their Afghan allies developed a special weapon that would lob four or five grenades at a time into the caves, the colonel says. After that, he recalls, the rebels usually surrendered when cornered underground. The Soviets also fired Roman candles into caves, letting loose colorful stars and a piercing siren sound. The candles were virtually harmless but terrified cave dwellers. "The Soviets found the unsuspecting foe covering his head with his arms," Jalali and Grau wrote

Rooting the rebels out of caves was still a deadly business. The mujahedin would booby-trap caves with mines, which would explode when Soviet soldiers tried to enter. David Grange, a retired Army general and ex-Ranger and Green Beret, warns that U.S. forces must not enter the mountains, looking blindly for caves. "You'd have people getting lost in minefields," he says. "It would spoil on you. It's a big place." So, Afghans say, the U.S. must ally itself with former rebels who can locate the right caves.

Qaumi, who has ties to the anti-Taliban Northern Alliance, says: "Without the help of these Afghans, America cannot do anything." The Soviets, he says, "had very great fighters... But we were strong Muslims, and it was our territory."

Bunker busting bomb

Screen Shot: Hyper Lander 2 Classic

'Tora Bora Fortress'- Hall of the Mountain King

Extracting Osama Bin Laden from the network of fortified caves and tunnels near Tora Bora, where the al-Qaeda leader is rumoured to be hiding, would be a formidable challenge for US forces.

The cave complex, overlooking the village about 35 miles [56km] south west of Jalalabad, was used by mujahideen forces fighting Soviet troops during the 1979-89 war.

Heavily fortified, the base was built in existing caves with covert assistance from the US. Russian troops failed to destroy the complex, which has been described as "the last word in Nato engineering". There have been unconfirmed sightings of Bin Laden in the area.

The village of Tora Bora itself, which lies in the meeting place of two valleys in the deep mountains of Nangarhar province, has been described as "virtually impregnable". Reports, which cannot be independently verified, say Bin Laden has been sighted in the area travelling at night by horseback and protected by 2,000 heavily-armed al-Qaeda fighters.

The fortified caves are thought to contain ammunition and storage depots for sheltering, supplying and replenishing a guerrilla army. The caves are said to be heated against the harsh Afghan winter, and have their own ventilation systems.

An arsenal of of US surface-to-surface 'stinger' missiles, which were extremely effective against Russian armour during the 1980s, is also believed to be stored there. Remote location The base, which is surrounded by deep forests, can only be reached on horseback. The main access to the complex is via a series of mule trails, which are primarily used as supply lines from remote northern Pakistan.

B-2 bombers could be used to drop bunker busting bombs The US has been targeting the area with GBU-28 bunker busting bombs, which can 'burrow' up to 100ft underground before detonating. However, it is thought that the construction of the caves, with rooms located at right angles from a main access tunnel, protects the main areas from missiles.

Unmanned 'Predator' spy planes equipped with heat-detecting sensors have been scanning the area searching for tell-tale heat emissions from the caves, which remain warm as surface temperatures fall.